Group size estimator

How many trainers do I need to invite?

The Estimator is already "trainers of this attacker needed to finish inside the timer", so this page does not invent a number: it reads it off the boss's own ranked counter list for three realistic parties and re-simulates each of them at every level from 20 to 50.

Raid bossTierIVsWeatherFriendshipDodgingShadow attackersMega attackersLegendary attackers

Invite 1 to be safe — 1 if everyone is prepared

At level 40, a party of Natu's top six counters needs 0.63 trainers (round up: 1), and a mixed lobby of ranks 13-24 needs 0.80 (round up: 1). The raid timer is 180 seconds and one prepared trainer alone would take 1:51. A prepared solo becomes possible at level 20. A duo works from level 20.

Natu · Shadow Tier 3

psychicflying

Weak to

rockghostelectricicedark

Boss CP: 9,610
Boss HP: 4,000
Raid timer: 180s
Party used: 6

Trainers needed, by attacker level

Scroll sideways for the mixed-lobby column.

Trainers needed to beat Natu at each attacker level
Attacker level	Six of the best counter	A prepared party	A mixed local group	Prepared solo time	Faints per timer
Level 20	1(0.85)	1(0.91)	2(1.14)	2:39	5.2
Level 25	1(0.76)	1(0.78)	1(0.98)	2:17	4.2
Level 30	1(0.67)	1(0.69)	1(0.87)	2:02	3.0
Level 35	1(0.62)	1(0.67)	1(0.84)	1:57	2.6
Level 40	1(0.60)	1(0.63)	1(0.80)	1:51	2.3
Level 45	1(0.59)	1(0.62)	1(0.77)	1:49	2.1
Level 50	1(0.58)	1(0.60)	1(0.74)	1:46	1.8

Whole trainers in bold, the raw estimator in brackets — 2.04 means two trainers is right on the line and three is comfortable.

Six of the best counter

Every trainer brings six copies of the single best counter — the theoretical floor.

1 trainer at level 40

Necrozma (Dawn Wings)0.60

A prepared party

Each trainer brings the boss's top six counters, powered up and correctly TM'd.

1 trainer at level 40

Necrozma (Dawn Wings)0.60
Kyurem (White)0.60
Regieleki0.63
Kyurem (Black)0.62
Thundurus (Therian)0.68
Zeraora0.67

A mixed local group

Ranks 13-24: reasonable but unoptimised parties, which is what a public lobby usually is.

1 trainer at level 40

Lunala0.79
Zamazenta (Crowned Shield)0.79
Absol0.78
Necrozma (Dusk Mane)0.78
Dragapult0.79
Glimmora0.80

The party these numbers assume

1. Necrozma (Dawn Wings)

Psycho Cut + Moongeist Beam

2. Kyurem (White)

Ice Fang + Ice Burn

3. Regieleki

Lock-On + Thunder Cage

4. Kyurem (Black)

Shadow Claw + Freeze Shock

5. Thundurus (Therian)

Volt Switch + Wildbolt Storm

6. Zeraora

Volt Switch + Plasma Fists

See the full ranked counter list for Natu · check a real lobby (win chance, who brings what) · make a share card of the top six

How this is worked out

The boss is ranked once at level 40 with rankCached (the same memoised call /raids makes), then the three bands — rank 1, ranks 1-6, ranks 13-24 — are re-simulated at each attacker level with an 8-run Monte Carlo each. Holding the party fixed and moving only its level is deliberate: it answers "what if my party were level 20" rather than "what would a level-20 player's completely different party be", and it is about ten times cheaper than re-ranking every attacker seven times. The Estimator itself is Pokebattler's definition, time to win including rejoin time divided by the raid timer.